Escape update: in this episode, The Doctor and Jo are taken back to Earth, transferred to a cell, marched to be questioned by the President, marched back to their cell, attempt to escape, fail, are marched to be questioned again by the President, during which The Doctor is kidnapped by the Draconians, Jo is recaptured by the Earth soldiers, questioned by the President, The Doctor is questioned by the Draconians, then escapes, then is recaptured himself by the Earth soldiers, and then, finally, at episode's end, it looks like the Ogrons are fixing to bust The Doctor and Jo out of their cell. Phew!
The action outlined above also pretty much describes all that went on in this episode. At the end of the installment, little has changed in our heroes' status. However, not only are The Doctor and Jo being used as pawns in a bigger game, the controller of which we have yet to see (although he does employ Ogrons), but they are being used as MacGuffins for both the humans and Draconians to capture and interrogate, which, in turn, lets us, the viewers, know more about each empire and their motives.
Despite the game of musical chairs played by The Doctor and Jo, and despite the fact that, after two episodes, Frontier in Space seems to be a directionless runaround, this is just so much fun - well shot, well designed, and, after a couple of missteps, a fine directorial effort from Paul Bernard.